Question

The matrix M= {{-4, -4, 0, 0},{-4,-4,0,0},{0,0,-4,-4},{0,0,-4,-4}}
has two distinct eigenvalues λ1<λ2. Find the eigenvalues and an orthonormal basis for each eigenspace.

Answer 1

I already have the first L eigenvalue and vector, but I cant seem to get the second eigenvector.